22021212210 has 128 divisors (see below), whose sum is σ = 55198900224. Its totient is φ = 5617946880.

The previous prime is 22021212209. The next prime is 22021212221. The reversal of 22021212210 is 1221212022.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 22021212210.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 34898595 + ... + 34899225.

It is an arithmetic number, because the mean of its divisors is an integer number (431241408).

Almost surely, 2^22021212210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22021212210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27599450112).

22021212210 is an abundant number, since it is smaller than the sum of its proper divisors (33177688014).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22021212210 is a wasteful number, since it uses less digits than its factorization.

22021212210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1208.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 22021212210 its reverse (1221212022), we get a palindrome (23242424232).

The spelling of 22021212210 in words is "twenty-two billion, twenty-one million, two hundred twelve thousand, two hundred ten".